Stephanie ate 5 slices of pie. Luis ate 5 slices. If Stephanie ate $\dfrac{5}{15}$ of the pie, what fraction of the pie was eaten?
Solution: If 5 slices represent $\dfrac{5}{15}$ of the pie, there must have been a total of 15 slices. $\text{fraction of pie eaten} = \dfrac{\text{number of slices eaten}}{\text{number of slices total}}$ They ate ${10}$ out of $15$ slices. They ate $\dfrac{10}{15}$ of the pie.